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Title: Electrothermal instability growth in magnetically driven pulsed power liners

This paper explores the role of electro-thermal instabilities on the dynamics of magnetically accelerated implosion systems. Electro-thermal instabilities result from non-uniform heating due to temperature dependence in the conductivity of a material. Comparatively little is known about these types of instabilities compared to the well known Magneto-Rayleigh-Taylor (MRT) instability. We present simulations that show electrothermal instabilities form immediately after the surface material of a conductor melts and can act as a significant seed to subsequent MRT instability growth. We also present the results of several experiments performed on Sandia National Laboratories Z accelerator to investigate signatures of electrothermal instability growth on well characterized initially solid aluminum and copper rods driven with a 20 MA, 100 ns risetime current pulse. These experiments show excellent agreement with electrothermal instability simulations and exhibit larger instability growth than can be explained by MRT theory alone.
Authors:
; ; ; ; ; ; ; ; ;  [1]
  1. Sandia National Laboratories, P.O. Box 5800, Albuquerque, New Mexico 87185-1186 (United States)
Publication Date:
OSTI Identifier:
22086145
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 19; Journal Issue: 9; Other Information: (c) 2012 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ACCELERATORS; ALUMINIUM; COPPER; CURRENTS; HEATING; IMPLOSIONS; LINERS; PLASMA SIMULATION; PULSES; RAYLEIGH-TAYLOR INSTABILITY; SANDIA NATIONAL LABORATORIES; SURFACES; TEMPERATURE DEPENDENCE